This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present invention. The following discussion is intended to provide information to facilitate a better understanding of the present invention. Accordingly, it should be understood that statements in the following discussion are to be read in this light, and not as admissions of prior art.
For existing cdma circuit-switched operations, the mobile station (MS) receiving a voice call request will only receive the calling party number (CPN) after the traffic channel has been established. The MS displays the CPN to the subscriber when the MS alerts the subscriber of the incoming voice call. Once alerted and the CPN is displayed, the subscriber can either accept or reject the voice call.
A single radio multi-mode mobile (SRMMM) is a mobile capable of supporting cdma circuit-switched operations over a circuit-switched RAT (e.g., 1×RTT) and packet-data operations over one or more packet-data radio access technologies (e.g., HRPD, eHRPD, LTE). A SRMMM can only be attached to one radio access technology at a time.
When a SRMMM (e.g., capable of cdma circuit-switched operation and packet-data operation on LTE) is attached to a packet-data RAT (e.g., LTE) it can receive cdma circuit-switched messaging using a specified tunneling protocol (e.g., Generic Circuit Services Notification Application (GCSNA)). A common reason for tunneling cdma circuit-switched messaging to a SRMMM attached to a packet-data RAT is the subscriber's telephone number (associated with the SRMMM) is homed on a cdma circuit-switched network element (e.g., a Gateway MSC). A Gateway MSC that homes a subscriber's telephone number implies that all voice call request (e.g., an ISUP Initial Answer Message) from a PSTN (Public Switched Telephone Network) to that telephone number will be routed to the Gateway MSC. If a voice call request from a PSTN has been routed to a Gateway MSC, the Gateway MSC will in turn discovers the Serving MSC serving the SRMMM (associated with the subscriber telephone number) and will route the voice call request to the Serving MSC. Tunneling of cdma circuit-switched messaging (e.g., initiated by a Serving MSC) to a SRMMM attached to a packet-data RAT proves a trigger to the SRMMM to detach from the packet-data RAT and attach to the circuit-switched RAT for the purpose of accepting a voice call request that had been routed to the Serving MSC.
When the SRMMM, attach to a packet-data RAT, receives a tunneled cdma circuit-switched Page Request message the SRMMM detaches from the packet-data RAT and attached to a designated circuit-switch RAT. Once a circuit-switched traffic channel has been established, the SRMMM displays the calling party number to the subscriber when the SRMMM alerts the subscriber (e.g., with an audio tone) of an incoming voice call. Only at this point can the subscriber reject the voice call.
At the time of receiving a tunneled cdma circuit-switched Page Request message the SRMMM is attached to a packet-data RAT (e.g. LTE) and may be on a critical active packet data session. Current existing procedures require the SRMMM upon receives a tunneled cdma circuit-switched Page Request message (e.g., 1× Page Request message) to retune and attach to the 1×cdma circuit-switched RAT. The SRMMM is then assigned a 1× circuit-switched traffic channel. The calling party number (CPN) is displayed to the MS user only after the SRMMM has acquired the 1× circuit-switched traffic channel. Only after the CPN has been displayed to the MS user can the MS User accept or reject the 1× voice call.
With the existing procedure, any user determined critical packet-data application might be terminated (e.g., due to a time-out condition) since the mobile is no longer attached to the packet-data system from the reception of the 1× Page Request message until the MS user rejects the 1× voice call (based upon the CPN). It is also inconvenient and a waste of 1× traffic channel resources for the SRMMM to fall back to 1× circuit-switched RAT every time a tunneled 1× Page Request message is received to determine whether the MS user is going to accept or reject the voice call.